The present invention relates to a new and improved valve assembly for use in an aircraft to control a flow of liquid through a drain conduit.
Lavatory and galley sink drains in an aircraft are commonly plumbed overboard or to a vacuum holding tank in either case, ambient cabin air will continuously flow down the open drain. The flow of cabin air through the drain creates an objectionable noise. In addition, the loss cabin air may create a slight turbine engine horsepower loss. When the aircraft is in an inactive condition on the ground, there may be a tendency for odors to reverse flow back up the sink drain line resulting in an odor problem in the galley or lavatory.